It was like a murder plot straight from a spy novel. Two young women approach a North Korean man in a busy Kuala Lumpur airport, smear a highly toxic chemical agent across his face and then flee. An hour later, the man is dead.

Then comes the explosive revelation: the murdered man was Kim Jong Nam – the half-brother of North Korea’s volatile leader, Kim Jong Un.

Catch this gripping story on Sunday 30 April at 18:30 CAT on Al Jazeera English (406).

“The murder shocked the world and exposed the inner workings of one of the world’s most secretive states,” said reporter Mary Ann Jolley. “It was clear there was a much bigger story to be told.”

In this compelling 101 East investigation, Jolley pulls back the layers of secrecy and paranoia that cloak North Korea’s ruling family to reveal what lay at the heart of this sensational murder.

Through interviews with North Korean defectors, former spies and other insiders, Jolley pieces together a portrait of a brutal leader who will stop at nothing – even killing his own relatives – to maintain his iron grip on power.

In an exclusive interview, North Korea’s highest profile defector, the former deputy ambassador to the UK, tells 101 East why Kim Jong Nam was high on the leader’s hit list.

“According to Kim Jong Un or the North Korean regime, Kim Jong Nam was a kind of physical hurdle which should be eliminated sooner or later,” explains Thae Yong Ho, who fled his post less than a year ago and is now under the protection of South Korea’s intelligence agency.

Kim Dong Shik, a former North Korean spy who defected after he was shot during a mission in South Korea, is adamant that the assassination would have been a direct order from the top. “There is only one person who can give that kind of order and it’s Kim Jong Un,” he says.

These insiders reveal why Kim Jong Un considered his half-brother such a threat that he had to be killed in a brazen assassination that sparked a fierce diplomatic storm.

With tensions rising on the Korean Peninsula, this compelling investigation exposes the ruthlessness and unchecked desire for power that have become the hallmarks of North Korea’s brutal leader.

North Korea: The Death of Kim Jong Nam screens on Al Jazeera English (406) at 18:30 CAT on Sunday 30 April 2017, on 101 East, Al Jazeera’s award-winning weekly current affairs programme focusing on a diverse range of stories across Asia and the Pacific.

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